EP0390882A1 - Moteur a piston alternatif. - Google Patents

Moteur a piston alternatif.

Info

Publication number
EP0390882A1
EP0390882A1 EP19890909535 EP89909535A EP0390882A1 EP 0390882 A1 EP0390882 A1 EP 0390882A1 EP 19890909535 EP19890909535 EP 19890909535 EP 89909535 A EP89909535 A EP 89909535A EP 0390882 A1 EP0390882 A1 EP 0390882A1
Authority
EP
European Patent Office
Prior art keywords
pendulum
piston
pendulum piston
piston machine
connecting rod
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
EP19890909535
Other languages
German (de)
English (en)
Other versions
EP0390882B1 (fr
Inventor
Willi Ernst Salzmann
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Salzmann Willy Ernst
Original Assignee
Individual
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Individual filed Critical Individual
Publication of EP0390882A1 publication Critical patent/EP0390882A1/fr
Application granted granted Critical
Publication of EP0390882B1 publication Critical patent/EP0390882B1/fr
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01B—MACHINES OR ENGINES, IN GENERAL OR OF POSITIVE-DISPLACEMENT TYPE, e.g. STEAM ENGINES
    • F01B9/00—Reciprocating-piston machines or engines characterised by connections between pistons and main shafts and not specific to preceding groups
    • F01B9/02—Reciprocating-piston machines or engines characterised by connections between pistons and main shafts and not specific to preceding groups with crankshaft
    • F01B9/026—Rigid connections between piston and rod; Oscillating pistons
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02F—CYLINDERS, PISTONS OR CASINGS, FOR COMBUSTION ENGINES; ARRANGEMENTS OF SEALINGS IN COMBUSTION ENGINES
    • F02F1/00—Cylinders; Cylinder heads 
    • F02F1/18—Other cylinders
    • F02F1/183—Oval or square cylinders
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02F—CYLINDERS, PISTONS OR CASINGS, FOR COMBUSTION ENGINES; ARRANGEMENTS OF SEALINGS IN COMBUSTION ENGINES
    • F02F3/00—Pistons 
    • F02F3/0015—Multi-part pistons
    • F02F3/0023—Multi-part pistons the parts being bolted or screwed together
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01B—MACHINES OR ENGINES, IN GENERAL OR OF POSITIVE-DISPLACEMENT TYPE, e.g. STEAM ENGINES
    • F01B11/00—Reciprocating-piston machines or engines without rotary main shaft, e.g. of free-piston type
    • F01B11/004—Reciprocating-piston machines or engines without rotary main shaft, e.g. of free-piston type in which the movement in the two directions is obtained by two single acting piston motors, each acting in one direction
    • F01B2011/005—Reciprocating-piston machines or engines without rotary main shaft, e.g. of free-piston type in which the movement in the two directions is obtained by two single acting piston motors, each acting in one direction with oscillating pistons, i.e. the pistons are arranged in ring like cylinder sections and oscillate with respect to the center of the ring
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02F—CYLINDERS, PISTONS OR CASINGS, FOR COMBUSTION ENGINES; ARRANGEMENTS OF SEALINGS IN COMBUSTION ENGINES
    • F02F2200/00—Manufacturing
    • F02F2200/04—Forging of engine parts
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
    • F05C—INDEXING SCHEME RELATING TO MATERIALS, MATERIAL PROPERTIES OR MATERIAL CHARACTERISTICS FOR MACHINES, ENGINES OR PUMPS OTHER THAN NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES
    • F05C2201/00—Metals
    • F05C2201/04—Heavy metals
    • F05C2201/0433—Iron group; Ferrous alloys, e.g. steel
    • F05C2201/0448—Steel

Definitions

  • the present invention relates to an improvement on a pendulum kol benmaschi ne.
  • a pendulum piston machine is known for example from WO 88/06675.
  • the machine has at least one pendulum piston fixed to a connecting rod, the edge of which runs in a preferably curved cylinder.
  • the object of the present invention to improve the design of the pendulum piston ben aschi ne in such a way that the unavoidable lateral mass acceleration that occurs occurs as little as possible, the remaining lateral displacement of the piston by corresponding design of the sealing elements of the displacements can pick up and guide the piston. Because of the described lateral displacement, the displacement path of the sealing elements is considerably greater than in known piston machines, in which the sealing elements only have to be displaced in the region of slight play and the additional wear that occurs.
  • FIG. 8 shows an enlarged detail of the piston guide and sealing element according to FIGS. 7 and
  • FIG. 1 a shows the movement curve of the piston center 1, the lateral displacement being shown in a five-fold increase.
  • the top dead center is designated 2, the bottom dead center 3.
  • the cylinder walls 4 are curved for geometric reasons so that the distance between the face seals remains constant during the course of the movement.
  • the elongated figure-of-eight curve results, which is traversed when the crankshaft runs clockwise according to the arrows.
  • the maximum horizontal amplitude of this curve is approximately 0.8% of the piston stroke and is therefore very small.
  • the curve according to FIG. 1a is described from the center of a piston, the end seals of which do not move relative to the piston.
  • FIG. 1a shows the movement curve of the piston center 1, the lateral displacement being shown in a five-fold increase.
  • the top dead center is designated 2, the bottom dead center 3.
  • the cylinder walls 4 are curved for geometric reasons so that the distance between the face seals remains constant during the course of the movement.
  • FIG. 1b shows the trajectory of the center of a pendulum, the end seals of which are freely movable relative to the piston. This curve corresponds to an abstraction in gravity-free space.
  • the elongated figure eight according to FIG. 1b is achieved with an optimal counterweight and shows the cam path of the piston center 1 above the piston stroke with the unguided, freely movable pendulum piston ben. It was determined mathematically and experimentally, and it was shown that it In the opposite sense, the curve is traversed as the essentially slender figure-eight curve according to FIG. A smaller increase in the counterweight results in an asymmetrical figure-eight curve according to FIG.
  • the cylinder crankcase 5 according to FIGS. 2 and 3 has curved cylinder walls 4 which connect to an internally circular crankcase 6.
  • This is articulated on the crank pin 10 and is so large in diameter that it acts as an optimal counterweight.
  • the connecting rod shaft 8 is hollow and therefore light.
  • a unit 7-9 intended as a straight rod (pendulum olben - connecting rod shaft - counterweight)
  • one rod end runs through the movement curve according to FIG. 1b if the length of the counterweight is exactly one third of the rod length.
  • the unit 7-9 can be cast or forged from two half parts which abut one another in the pendulum plane 11 or the normal plane 12 and are connected to one another.
  • the sealing strips 14 are slidably mounted and connected to one another by compression springs 15.
  • These springs 15 are axially displaceably mounted in the longitudinal bores of the pendulum piston and cause the sealing strips 14 to bear continuously against the cylinder walls 4.
  • Shorter compression springs 16 are supported in the blind holes of the pendulum piston, which reach only approximately to the center of the piston, and are supported in their bases and serve to center the piston laterally within the cylinder walls 4 Spring detection and pretensioning ensure that the pendulum piston runs safely and with as little friction as possible, the center point 1 of which, as the speed increases, runs on movement curves between Fig.la to approximately Fig. 1b.
  • Two or more helical springs 15 and / or 16 can be arranged coaxially one inside the other or can be replaced by other elastic means.
  • the housing 5 is machined from the front. After disassembly of the inner flat front cover 17, the only two movable main parts of the engine, namely the unit 7-9 and the crankshaft 18 with counterweight 19 mounted on both sides of the friction roller 20, are easily accessible.
  • FIG. 6 this is done analogously to FIG. 2a by coil springs 15, which, however, are not stored in bores, but in milled grooves 36 of the pendulum piston 37.
  • This requires a removable piston head 38, which allows simple replacement of the piston guide and sealing elements from above.
  • the central screw 39 serves as a center stop which is provided with a gap 40. wound piston guide spring 41.
  • FIG. 7 shows a very simple, elastic piston guide by means of gas-filled spring elements 50 arranged on the end face made of highly heat-resistant, flexible material, for example PTFE.
  • These cushion-like spring elements 50 guide the piston diametrically via end strips 51 and set the closed ends of the side sealing strips 52, at the same time sealing the overlapping joints of the sealing strips 51 and 52.
  • These gas-filled spring elements thus replace the otherwise usual wave springs.
  • a removable piston head 38 is unnecessary for assembly reasons and also because this progressive and silent air suspension means that a long service life can be expected.
  • the inner flanks 53 of the end strips 51 and the base 54 of their guide grooves 55 must have a claw-shaped profile, according to FIGS. 8A and 8B, to which the cushion 50 clings wrinkle-free when pressed (FIG. 8B), and the Schl also shaped cover of the cushion 50 must be wrapped with stretchable fabric, for example made of carbon or Kevlar fibers.
  • the connecting rod shaft 60 with support and cooling ribs 61, is hollow cast, the core is supported by the opening 62, which is turned off by the semicircular gas slide 63.
  • the connecting rod shaft 60 ends in the upper half 66 of the connecting rod eye, the large diameter of which is hindered by dynamic demands, as explained under FIGS. 2 and 3.
  • the connecting rod cover 67 with balancing holes 67 ' is fastened by screws 68, the countersinks 69 of which are rendered harmless by a cover tape 70 with a tensioning screw 71.
  • the cover band 70 can have fine transverse grooves 72 with a labyrinth effect on the outside, especially if it consists of plastic instead of steel.
  • the large diameter of the connecting rod eye 66, 68 results in a large inner diameter of the crankcase, which is closed by the cover 32.
  • the pumping work is partially recovered from "top" dead center (FIG. 4) to point 73.
  • the throttle valve is not in the intake manifold 74, but in the form of two Um connected by a long hub! uf.tkl appen 75 directly behind the side flushing channels 78.
  • the cylinder is switched off or the engine is idling 75 ', almost the full amount of charge air is returned to intake 79 and recirculated with little loss.
  • Channels 80 lead from the flushing channels 78 to the Low pressure injector 81 (air wrap of the jet).
  • grooves 82 of the connecting rod eye and bores 83 and 84 which are arranged at a suitable location, can be used to meter the lubricating oil as required (recirculation flaps 75) and to be sucked in without a pump.
  • Minimum oil consumption (the aim is to achieve a per mille) is the top priority for two-stroke engines today, which is probably only possible with low-friction floating pistons (the sealing strips of which may even have rotating ceramic needles).
  • the position of the engine in the room is also decisive for lubrication and piston travel, preferably inclined to the left in FIGS. 4 and 2 (by approximately 15 ° to 150 °).
  • the elastic motor fastening can take place on threaded eyes 82 of the lower part 32.
  • the cylinder head 31 is made, for example, of cast iron or ceramic, cermet without liquid cooling, and is therefore very easy to disassemble .
  • Dr. Merritt from Coventry Polytechnic, it contains a combustion chamber formed by the trough 83 and the plate 84, which is at least partially filled, for example, with heat-resistant steel wool 85, some of which or completely coated with precious metal.
  • this combustion chamber is ideally flowed through in direct current by the charge, which ignites at start and low load on the spark plug 86, but otherwise on the steel wool 85 (secondary ignition with catalytic Combustion). This should result in the lowest fuel consumption and save an external catalytic converter.
  • the elongated, cylindrical combustion chamber of FIGS. 11 and 12 of WO 88/06675 is also of interest, in particular in connection with direct injection (diesel, gasoline, gas or multi-substance).
  • direct injection diesel, gasoline, gas or multi-substance
  • a conventional, hemispherical and / or semi-cylindrical combustion chamber according to FIG. 3 is also possible.
  • the round pendulum piston 88 with a connecting rod 89 and counterweight 90 is suitable for four-stroke engines of all kinds.
  • a tried and tested seal consists of the guide ring 90 with an overlapped joint 91 in the transverse plane 92 and a radially freely movable one above it Feuerring 93 and an oil ring 94.
  • the elastic Kol ben Installation takes place through two semi-circular, gas-filled pressure hoses 95, which are surrounded by a flexible band 96, for example made of PTFE.
  • a corrugated profile of the inside of the band and the bottom of the groove, analogous to FIG. 8, is advantageous.
  • the pendulum piston 88 can also have, for example, a square layout (suitable for four valves).
  • Figures 9 and 10 also stand for, but only single-stage and therefore voluminous compressors.
  • a two-stage high-performance compressor can be derived from the internal combustion engine according to FIGS. 3 and 4.
  • a wider, preferably quadratic pendulum piston and a much larger overflow slot 97 serve for this purpose, and if necessary an end channel 98.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Pistons, Piston Rings, And Cylinders (AREA)
  • Fluid-Damping Devices (AREA)
  • Forklifts And Lifting Vehicles (AREA)
  • Shafts, Cranks, Connecting Bars, And Related Bearings (AREA)
  • Compressor (AREA)
  • Lubrication Of Internal Combustion Engines (AREA)

Abstract

Un moteur à piston alternatif comprend un carter de cylindre (5) dont les parois de cylindre (4) sont courbes et un carter interne circulaire (5) contenant un piston alternatif (7) à corps de bielle intégré (8) et un oeil circulaire (9) de tête de bielle qui sert de contrepoids. Le centre (1) du piston peut ainsi décrire des courbes de forme déterminable, de sorte que le piston alternatif (7) peut effectuer un mouvement oscillant sous l'effet de forces latérales minimes. Les amplitudes latérales importantes qui en résultent exigent des profilés d'étanchéité spéciaux (14) avec des ressorts de compression (15) correspondants.
EP89909535A 1988-09-07 1989-09-07 Machine a piston pendulaire Expired - Lifetime EP0390882B1 (fr)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
CH334888 1988-09-07
CH3348/88 1988-09-07
PCT/CH1989/000165 WO1990002867A1 (fr) 1988-09-07 1989-09-07 Moteur a piston alternatif

Publications (2)

Publication Number Publication Date
EP0390882A1 true EP0390882A1 (fr) 1990-10-10
EP0390882B1 EP0390882B1 (fr) 1996-05-15

Family

ID=4254031

Family Applications (1)

Application Number Title Priority Date Filing Date
EP89909535A Expired - Lifetime EP0390882B1 (fr) 1988-09-07 1989-09-07 Machine a piston pendulaire

Country Status (6)

Country Link
EP (1) EP0390882B1 (fr)
JP (1) JPH03501044A (fr)
AT (1) ATE138154T1 (fr)
AU (1) AU4075489A (fr)
DE (1) DE58909682D1 (fr)
WO (1) WO1990002867A1 (fr)

Families Citing this family (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4400132C1 (de) * 1994-01-05 1995-03-09 Daimler Benz Ag Stirnwandaufbau für einen Kraftwagen mit vorn angeordneter Antriebseinheit
CN1171143A (zh) * 1994-12-24 1998-01-21 维利·E·扎尔茨曼 摆动活塞式发动机和摆动活塞式压缩机
JP5094349B2 (ja) * 2007-11-30 2012-12-12 株式会社日立産機システム シリンダ装置、圧縮機およびシリンダ装置の製造方法
DE102008045580B3 (de) * 2008-01-10 2009-05-07 Manfred Wanzke Pleuelkolbenkompressor
DE102009005397B4 (de) 2009-01-19 2011-02-17 Manfred Wanzke Pleuelkolbenkompressor mit drehteilsegmentförmiger Dichtung
GB2528748B (en) * 2014-06-03 2016-08-17 Pattakos Manousos Asymmetric transfer and intake in two-strokes
JP6321700B2 (ja) * 2016-02-26 2018-05-09 三菱重工業株式会社 油圧機械および風力発電装置

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1380659A (en) * 1916-04-26 1921-06-07 Layman Pressed Rod Company Inc Link, lever, and the like
DE2161841A1 (de) * 1971-12-13 1973-06-20 Ewald Harr Kreiskolben-brennkraftmaschine
JPS6041202B2 (ja) * 1976-11-25 1985-09-14 有限会社内木場エンジン研究所 ロツキングピストンエンジン
CH629286A5 (en) * 1977-02-24 1982-04-15 Salzmann Willi Ernst Self-aligning-piston machine
DE2915848A1 (de) * 1979-04-19 1980-11-06 Helmut Thurner Verdichter- und sauggeraet und kolben fuer dieses geraet
DE3542071A1 (de) * 1984-12-08 1986-06-12 Volkswagen AG, 3180 Wolfsburg Pleuelstange

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO9002867A1 *

Also Published As

Publication number Publication date
WO1990002867A1 (fr) 1990-03-22
EP0390882B1 (fr) 1996-05-15
ATE138154T1 (de) 1996-06-15
JPH03501044A (ja) 1991-03-07
DE58909682D1 (de) 1996-06-20
AU4075489A (en) 1990-04-02

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